Maintenance
Coaxial RF Power Standards Instruction and Service Manual
5-10
Gamma Corrections (optional)
This part of the procedure is optional and only applies if the Reflection Coefficient magnitude (
ρ
)
and angle (
φ
) was measured and recorded during the Power Splitter Calibration. The Reflection
Coefficient magnitude (
ρ
) and phase angle (
φ
) must also be known for the Reference RF Power
Standard.
TEGAM strongly recommends applying Gamma Corrections as it will provide a
more accurate calibration with the lowest uncertainty.
10.
Apply Gamma Corrections to the calibration factor of the Working Standard at each
frequency by:
Corrected K
2
= K
2
|1 -
Γ
1
Γ
2
|
2
Where:
Corrected K
2
= cal factor of the Working Standard after Gamma correction is applied,
K
2
= cal factor of the Working Standard before Gamma correction is applied,
Γ
1
= reflection coefficient of the Reference Power Standard,
Γ
2
= reflection coefficient of the Working Standard
The same formula in terms of magnitude (
ρ
) and phase angle (
φ
):
Corrected K
2
= K
2
(1 –
ρ
1
ρ
2
cos(
φ
1
+
φ
2
))
2
+ (
ρ
1
ρ
2
sin(
φ
1
+
φ
2
))
2
Where:
Corrected K
2
= cal factor of the Working Standard after Gamma correction are applied,
K
2
= cal factor of the Working Standard before Gamma correction is applied,
ρ
1
= reflection coefficient magnitude of the Reference Standard,
φ
1
= reflection coefficient phase angle of the Reference Standard,
ρ
2
= reflection coefficient magnitude of the Working Standard,
φ
2
= reflection coefficient of the phase angle Working Standard.
